Where to place the chair when praying seated in congregation

Question: Whoever prays sitting on a chair in the masjid, should he place the back legs of the chair in line with the [other] people praying, or should he place the front legs [of the chair] in line with the feet of the people praying [in his row]?

Response: He should place the back legs of the chair in line with the feet of the people praying [in his row].

Question: But when he stands, he will be infront of the [rest of the] row.

Response: He is not standing, [so he should place] his bottom [on the chair] in line with the feet of the people praying [in his row].